Oculus: Origin, Characteristics, Types, Examples

Oculus refers to the hole in a circular or oval shape that functions as a window or as a passage of light, although its function can also be purely decorative. At present, it does not have a definition in the Dictionary of the Royal Academy but it is a term widely known in architecture.

Etymologically, the word derives from the Latin expression “ochulos” which is literally translated as “eye”. Even, in Anglo-Saxon speech, it serves to specifically qualify this type of architectural structure.

Although it can be considered as a variety of window, some specialists indicate that the oculi were used to lighten the weight of the domes, while allowing the passage of air and light within the enclosure.

On the other hand, there are records that the first appearances of this architectural element occurred in Roman and Greek constructions, whose influence spread in the different artistic movements and which persist in our days.


The oculus is an architectural expression that, according to records, has been present in culture and art since prehistory, especially in Western Europe. This possibly occurred because it was an easily replicable geometric figure present in nature.

During the Neolithic, the oculus was included as a symbol of the gods’ constant vigilance and attention to the actions of human beings.

However, it was not until the Middle Ages , specifically during the Romanesque and Gothic periods, when the oculus became popular in the constructions of basilicas and other religious enclosures.

Likewise, its presence gained strength in the Renaissance , because it helped to provide balance in the domes, while allowing light and air to enter.

Thanks to the prominence of this architectural element in different constructions, other variations of it emerged, such as the “rose window” and the “lantern”.


Some important aspects can be pointed out:

-It began to be included in the architectural details from the 16th century, although its antecedents date back to Prehistory.

-The “rose window” is a type of oculus that became popular during the Gothic period.

-In some cases, the oculus is also known as a “bull’s eye”. However, some specialists prefer to treat it as a subtype of the former rather than an equivalent term.

-In French architecture, oculi stand out for being in the attics (or attics) in different types of buildings.

-It is also common to see oculi in the domes, this is mainly due to the fact that the architects discovered that it allowed the correct distribution of weight, thus reducing the possibility of collapse.

-Nowadays, it is possible to find oculi in boats, hospitals and airplanes for structural reasons.

-This architectural element can be found more frequently in religious enclosures.

-From the point of view of archeology, the oculus is associated with the eye of the god or of the goddess, which remains vigilant before the actions of human beings.


Three types of oculi can be highlighted to be explained below:


As noted above, some authors refer to it as a type of small oculus, primarily intended as a window. It first appeared in architecture in the 16th century.


It is a type of circular window arranged radially with the appearance of a “rose”, and accompanied by glass with religious motifs. Initially, the rosettes were small but they gained size and importance with the passage of time. Even his designs became more intricate and complex.

Like most oculi, the “rose window” is a type of architectural element present in religious rooms with different motifs drawn from the scriptures, with the aim of causing an impact among the faithful.


Architecturally, its function is more or less similar to an oculus, but it is arranged in the shape of a tube in order to serve as the top of a dome. The function is considered to be purely decorative.

Real examples

-In the bell tower of the Giralda or in the facade of the Plaza de Toros, in Seville, Spain, it is possible to see examples of oculi.

-Other examples to cite are: the tower-facade of the Church of Santa María de Utrera and the facade of the Church of Our Lady of Oliva de Lebrija.

-In the Roman Pantheon (built in the 27th century BC) there are oculi, which were used to allow the passage of light and air.

-As for lanterns, some examples can be found: in St. Peter’s Basilica in Rome, in the Church of San Frediano in Cestello and also in the Washington Capitol. In Latin America, one of the best known is the Dome of the Metropolitan Cathedral, in Mexico City.

-Studies consider that rose windows are one of the most beautiful architectural elements that exist. Some of the most notable examples are the three rose windows located in Notre Dame, the Gothic Eye in the Cathedral of Santa María in Palma de Mallorca and in the Cathedral of Seville.

-Although the oculus is an architectural resource present in Christian art, it can also be found in other cultural manifestations such as in the dome of the Hasht Bihisht palace in Iran, or in the bronze bowl found in Los Millares in Almería, Spain.

Some terms in architecture

Some definitions can be noted below:

Abside : it is called the most sacred area of ​​a church, since the altar is located and is located on the crypt destined to house the remains of the saints.

Plataresco : it is a Spanish architectural style that combined Gothic and Renaissance elements and forms. The motifs were finely carved and with pronounced details.

Triforium : these are ornamental windows located on the arches of the side naves of the churches.

Arch : it is a support element generally curved, since it draws a semicircular or elliptical shape.

Caryatid : it is a column with the figure of a woman in Greek temples. These figures were so influential that they were also used during the Renaissance era.

Crestería : it is a decorative element used as an architectural finish present, especially, on the facades or ceilings. It was extremely popular during the Gothic period.


  1. Definition of oculus. (sf). In Definition.of. Retrieved: October 02, 2018. In Definition.de de definition.de.
  2. Lantern. (sf). On Wikipedia. Retrieved: October 02, 2018. In Wikipedia at es.wikipedia.org.
  3. Rosette. (sf). On Wikipedia. Retrieved: October 02, 2018. In Wikipedia at es.wikipedia.org.
  4. Oculus. (sf). In Arqhys. Retrieved: October 2, 2018. In Arqhys de arqhys.com.
  5. Oculus. (sf). In SevillaPedia. Retrieved: October 2, 2018. In SevillaPedia de sevillapedia.wikanda.es.
  6. Oculus. (sf). On Wikipedia. Retrieved: October 02, 2018. In Wikipedia at es.wikipedia.org.
  7. Bull’s-eye. (sf). On Wikipedia. Retrieved: October 02, 2018. In Wikipedia at es.wikipedia.org.
  8. Vocabulary of architectural and artistic terms. (sf). In Vocabulary of architectural and artistic terms. Retrieved: October 2, 2018. In Vocabulary of architectural and artistic terms of epapontevedra.com.

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